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排序方式: 共有1957条查询结果,搜索用时 31 毫秒
1.
neurogenetics - Charcot-Marie-Tooth (CMT) disease is the most common inherited neuropathy with a prevalence of 1 in 2500 individuals worldwide. Here, we report three Turkish siblings from...  相似文献   
2.
Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment.  相似文献   
3.
Ligneous periodontitis (LP) is a rare periodontal disease in which plasminogen deficiency and fibrin deposition both play a part, resulting in characteristic gingival enlargement and periodontal breakdown. Recent data suggest that oxidant/antioxidant changes are significant in the pathology of oral diseases. This study examines the gingival histopathology in 2 cases with LP. To examine the antioxidant (AO) status, the activity of the major AOs glutathione (GSH), catalase (CAT), and glutathione S-transferase (GST) and the malondialdehyde (MDA) levels, a product of lipid peroxidation, were measured and compared with healthy control subjects. The histopathologic examination of the gingiva revealed subepithelial fibrin accumulation and irregular extensive downward proliferation of the epithelium. Biochemical analysis showed that the CAT, GST, and MDA levels were higher in LP patients than in the control subjects, and the GSH level was lower. Our preliminary findings show that in LP, the AO capacity of the gingiva changes or decreases and lipid peroxidation increases, which suggests that oxidative stress is involved in the pathology of the periodontal breakdown observed in this disease.  相似文献   
4.
BACKGROUND: The purpose of this study was to determine the rate of spontaneous gestational sac loss during the first trimester in women achieving multiple pregnancies by ICSI. METHODS: A retrospective analysis was performed of 1448 consecutive multiple pregnancies conceived by ICSI. RESULTS: Of the cohort of 1448 pregnancies, twin gestations constituted 59.6% (864), triplets 30.2% (438) and quadruplets 10.0% (146). During the first trimester, 69 (4.7%) patients miscarried, while 179 (12.3%) continued their pregnancies and had fewer gestational sacs at the end of the first trimester than at the beginning. The overall loss rate of any gestational sac during the first trimester in these multiple pregnancies was 10.1%. There was a significant difference in the frequency of spontaneous reduction to twin or singleton pregnancies in the first trimester between women carrying triplets (11.7%) and those carrying quadruplets (3.5%) [P = 0.004; odds ratio (OR) 3.5; 95% confidence interval (CI) 1.3-9.1]. The frequency of gestational sac loss was significantly greater among women >35 years old (20.9%) than in women less than 35 years old (15.9%) (P = 0.03; OR 1.4; 95% CI 1.0-1.9). CONCLUSION: In multiple pregnancies there is a significant risk of spontaneous loss of any embryo during the first trimester. These findings should be considered prior to any decision about selective embryo reduction.  相似文献   
5.
Based on direct sequencing information from 5UTR and NS5B regions, we identified subtype 1b as a predominant hepatitis C virus genome in Turkey, which affected more than 91% of 79 patients studied. Next, the full genome sequence of a Turkish 1b isolate was obtained by the cloning of polypeptide-encoding region into 7 overlapping fragments. Turkish 1b isolate, which was named HCV-TR1, comprises 9361 nucleotides, including 306 nucleotides of 5UTR, a single long open reading frame of 9033 nucleotides, and 22 nucleotides of 3UTR. When compared to HCV 1b polypeptide sequences available at GenBank, the predicted polypeptide displayed a total of 36 amino acid substitutions, of which 16 was specific for HCV-TR1 isolate. Despite these changes, major structural and functional motifs of HCV proteins were maintained in HCV-TR1. In contrast, HCV-TR1 displayed amino acid substitutions in 6 out of 9 major cytotoxic T-cell epitopes. These data suggest that HCV-TR1 encodes functionally intact viral proteins, but it also encodes altered viral epitopes, which may affect host immune-response.  相似文献   
6.
Male infertility affects approximately 30% of infertile couples. As spermatozoa mature in the epididymal lumen, their potential for mobility increases, and their protein, lipid and small RNA (sRNA) content changes, whereas capacitation and fertilisation take place in the female reproductive tract. Both of the latter processes are affected by maturation, because impaired maturation causes premature capacitation and fertilization. The epididymis produces a suitable environment for sperm maturation via ion transport, vesicle secretion and protein matrix formation. The microenvironment for sperm maturation varies in three broad segments: the caput, the corpus and the cauda epididymis. Epididymosomes transfer proteins, lipids and sRNAs from the epididymal epithelium to spermatozoa and genetic alterations of epididymal genes can lead to decreased sperm motility, morphological abnormalities of spermatozoa and subfertility. Genetic factors are involved in all aetiological categories in male infertility. However, studies conducted on the genes involved in epididymal functions are limited. The sRNA content of spermatozoa changes during epididymal migration, and these sRNAs play a role in embryo development and epigenetic inheritance. This review aims to clarify the role of the epididymal epithelium in the maturation of spermatozoa in light of the current molecular genomic knowledge.  相似文献   
7.
Archives of Sexual Behavior - Male couples in open relationships tend to have as equally fulfilling relationships as monogamous male couples; however, less is known about communication differences...  相似文献   
8.
In the present study, we tried to determine whether IUD insertion related PID and febrile complications could, be prevented by prophylactic use of antibiotics. We studied 300 patients who were admitted to our family planning clinic for IUD contraception. Of these, 150 patients received prophylactic Doxycycline (group 1) and the second 150 received no therapy (group 2). Five cases experienced fever with or without leucocytosis and none required hospitalization. PID was observed in one woman in each group.Positive culture (gonorrhea) was obtained in one woman who was then treated by relevant, antibiotics; the other woman required hospitalization for two days. The overall infection rates for group 1 and 2 were 2.1% and 2.9%, respectively and this difference was not significant. The incidence of PID infection and febrile complications was found to be very low for both groups when compared to other studies, suggesting that aseptic conditions with proper insertion reduce the risk of infection.
Resumen En el presente estudio, intentamos determinar si la inflamación pélvica y las complicationes febriles relacionadas con la inserción, de DIU podían evitarse mediante la administración profiláctica de antibióticos. Estudiamos a 300 pacientes de nuestra clínica de planificación familiar que recibieron DIU. Se administró un tratamiento profiláctico de doxicilina a 150 pacientes (Grupo 1) mientras que las restantes no recibieron ningún tratamiento (Grupo 2). Hubo cinco casos de fiebre con o sin leucocitosis pero ninguno requirió hospitalización. La inflamación pélvica se observó en dos casos, uno de cada grupo. Se obtuvo un cultivo positivo (gonorrea) en uno de los casos, que fue tratado con antibióticos apropiados, y el segundo caso debió ser hospitalizado durante dos días. Las tasas generales de infección fueron para el Grupo 1 y el Grupo 2, respectivamente, del 2,1% y del 2,9%, diferencia que no es significativa. Una comparación con otros estudios permitió verificar que la incidencia de infección pélvica inflamatoria y complicaciones febriles era muy baja en los dos grupos, lo cual hace pensar que las condiciones de asepsia y la inserción correcta reducen el riesgo de infección.

Resumé Dans la présente étude, nous avons tenté de déterminer si l'inflammation pelvienne et les complications fébriles liées à l'insertion de DIU pouvaient être évitées par une administration prophylactique d'antibiotiques. Nous avons suivi 300 patientes de notre clinique de planning familial, admises pour l'insertion, de DIU. Un traitement prophylactique de doxycycline a été administré à 150 de ces patientes (Groupe 1) et les autres n'ont reçu aucune, thérapie (Groupe 2). Nous avons eu cinq cas de fièvre avec ou sans leucocytose mais aucune de ces femmes n'a d être hospitalisée. L'inflammation pelvienne s'est manifestée dans deux cas, un dans chaque groupe. Une culture positive (gonorrhée) a été obtenue chez une de ces patientes, à laquelle un traitement aux antibiotiques appropriés a été administré, et la seconde a d être hospitalisée pendant deux jours. Les taux globaux d'infection ont été, respectivement pour le groupe 1 et le groupe 2, de 2,1% et 2,9%, ce qui ne représente pas une différence significative. Une comparaison avec d'autres études a permis, de constater que l'incidence d'infection pelvienne inflammatoire et de complications fébriles était très faible dans les deux groupes, ce qui laisse penser que les conditions d'asepsie et une insertion correcte réduisent le risque d'infection.
  相似文献   
9.
Spondylo-ocular syndrome is a rare autosomal recessive disorder characterized by generalized osteoporosis, hearing loss, visual impairment due to cataract, and platyspondyly. Previous studies have revealed that the syndrome is caused by pathogenic variants in the XYLT2 gene. A patient with spondylo-ocular syndrome and two heterozygous pathogenic variant in the XYLT2 gene in compound state are described here. The patient presented with osteoporosis, platyspondyly, ocular findings, hearing loss, kyphosis, scoliosis, facial findings, intellectual disability, and undescended testicles. Previous reports of bisphosphonate treatment response were variable, whereas a long-term follow-up with bisphosphonate treatment in this case resulted in normalization of vertebral structures. Reporting such cases helps to determine the appropriate genotype–phenotype correlation in patients with XYLT2-related pathogenesis.  相似文献   
10.
Effects of tobacco smoking and alcohol use on risks of cancers of thelarynx and lung have been evaluated extensively in industrialized countries.Few studies on the effect of these risk factors have been reported fromdeveloping countries. We conducted a case-control study to evaluate risks oflaryngeal and lung cancers in men by subsite and cell type in relation tosmoking and alcohol drinking in Turkey, a country where smoking and alcoholconsumption patterns are different from those in industrialized countries. Weidentified 832 laryngeal and 1,210 lung cancer cases and 829 controls withinformation on smoking and alcohol use (amount and duration) and histologiccell type from an oncology treatment center of a Social Security Agencyhospital in Istanbul, Turkey, admitted between 1979 and 1984. Both laryngealand lung cancer showed significant associations with smoking and alcoholdrinking, but no monotonic dose-response was obtained for alcohol drinking.Among smokers, the highest risks were observed in the supraglottis region ofthe larynx (odds ratio [OR] = 4.1) after adjustment for age and alcohol use.Among alcohol drinkers, the highest risks were observed in the glottis regionof the larynx (OR = 1.7) after adjustment for age and smoking. In theanalysis by the cell type of lung cancer among ever-smokers, small cell typeshowed the highest risk (OR = 5.4), while it showed no association withalcohol drinking. Cumulative cigarette use (pack-years) and number ofcigarettes per day showed stronger associations than years smoked for bothcancer sites. The relative risks of joint exposure to smoking and alcoholwere 12.2 for laryngeal cancer and 14.1 for lung cancer among heavy smokersand heavy alcohol drinkers. This study provides epidemiologic evidence fromTurkey that smoking and alcohol use are associated with risks of cancers ofthe larynx and lung.  相似文献   
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